Drip fertigation and crop management in Bt cotton (Gossypium hirsutum)

Abstract

A field experiment was conducted during the rainy season of 2014 and 2015 at Rahuri, Maharashtra, to study the effect of deficit irrigation, fertigation and planting techniques on growth, yield and quality parameters of Bt cotton (Gossypium hirsutum L.). Scheduling of irrigation at 1.0 ETc recorded significantly maximum growth, yield attributes and seed-cotton yield of Bt cotton, being at par with 0.8 ETc irrigation regime. Maximum and significantly higher seed-cotton yield was recorded in 1.0 ETc irrigation regime (3.3 t/ha), being at par with 0.8 ETc irrigation regime (3.1 t/ha) on pooled mean basis. Planting of Bt cotton at 90 cm × 90 cm was found superior to 150 cm × 60 cm in respect of growth, yield attributes and seed-cotton yield of Bt cotton. Planting of Bt cotton at 90 cm × 90 cm resulted in significantly higher seed-cotton yield (3.3 t/ha) than 150 cm × 60 cm planting (2.3 t/ha) on pooled mean basis. Fertigation of 100% GRDF up to 100 days + 20 kg MgSO4 /ha and 25 kg ZnSO4 /ha up to flowering at weekly interval + foliar spray of Fe (1.0 %) and B (0.5 %) at flowering and boll-development stages was found suitable for achieving the maximum growth, yield attributes and seed-cotton yield (3.1 t/ha) of Bt cotton. The maximum water use efficiency was obtained with 0.6 ETc irrigation regime (7.00 kg/ha-cm), followed by 0.8 ETc irrigation regime during both the years.